The Prophylactic Effect of Anti-influenza Agents for an Influenza Outbreak in a University Hospital.

Objective From November 24 to December 9, 2013, an outbreak of the influenza (flu) A (H3) virus occurred in a tertiary-care university hospital (1,014 beds). We herein report the prophylactic effect of anti-flu agents for controlling the flu outbreak. Methods We administered pre- or post-exposure prophylaxis with anti-flu agents in flu outbreak. To test the effectiveness of prophylaxis in a flu outbreak, we used the posterior mean of the reproductive value during the pre- and post-intervention period. We also simulated the probability distribution of new flu cases. We performed an analysis to quantify the strength of the intervention effect. Results A total of 97 people were diagnosed with flu before the intervention, and 7 were diagnosed after the intervention. A molecular analysis of the flu virus revealed that this outbreak was due to the flu A (H3) virus. A total of 3,702 people received prophylaxis. There was a significant reduction in the reproductive value from 1.89 [95% confidence interval (CI), 1.59 to 2.24] to 0.65 (95% CI, 0.02 to 1.00) after the intervention (p<0.001). Conclusion Prophylaxis with anti-flu agents, along with prompt identification and isolation of infected individuals, was effective in reducing the impact of a flu outbreak in a hospital.

Comparison of efficacy and safety of oseltamivir and zanamivir in pandemic influenza treatment.

AIM: In 2009, a flu pandemic caused panic worldwide. Oseltamivir and zanamivir were widely used in this pandemic. Currently, there are a limited number of studies comparing the efficacy and tolerability of these two drugs. This study aimed to compare the efficacy and tolerability of these two drugs in the treatment of influenza. MATERIALS AND METHODS: Patients diagnosed with influenza at our infectious disease outpatient clinic during the influenza season between October 1, 2009 and February 1, 2010 were included in the study. Study data were obtained retrospectively from files for consecutive patients. A total of 136 subjects were selected. After exclusion criteria were applied, 56 subjects were discarded. The information for 80 patients in whom oseltamivir or zanamivir therapy was initiated (40 for each therapy) was compiled, and the efficacy and tolerability of the drugs were compared. RESULTS: There was no significant difference in efficacy for the two drugs (P>0.05). Temperature normalization was significantly faster in patients taking zanamivir (P=0.0157). Drowsiness was the most frequent adverse event for both drugs (38% for the oseltamivir group, and 22% for the zanamivir group). Respiratory distress was observed in five patients in the zanamivir group, whereas it was not observed in patients in the oseltamivir group (P<0.05). One patient had to discontinue therapy in the zanamivir group due to respiratory distress. CONCLUSION: Efficacy (in terms of symptom relief and duration to resumption of work) and adverse events were similar for zanamivir and oseltamivir, but temperature normalization was much more rapid in patients using zanamivir. Patients using zanamivir should be monitored for respiratory distress.